@article{13525, abstract = {{The frequency-dependent dielectric function and the second-order polarizability tensor of ferroelectric LiNbO3 are calculated from first principles. The calculations are based on the electronic structure obtained from density-functional theory. The subsequent application of the GW approximation to account for quasiparticle effects and the solution of the Bethe-Salpeter equation for the stoichiometric material yield a dielectric function that slightly overestimates the absorption onset and the oscillator strength in comparison with experimental measurements. Calculations at the level of the independent-particle approximation indicate that these deficiencies are, at least, partially related to the neglect of intrinsic defects typical for the congruent material. The second-order polarizability calculated within the independent-particle approximation predicts strong nonlinear coefficients for photon energies above 1.5 eV. The comparison with measured data suggests that the inclusion of self-energy effects in the nonlinear optical response leads to a better agreement with experiments. The intrinsic defects of congruent samples reduce the optical nonlinearities, in particular, for the 21 and 31 tensor components, further improving the agreement between experiments and theory.}}, author = {{Riefer, Arthur and Sanna, Simone and Schindlmayr, Arno and Schmidt, Wolf Gero}}, issn = {{1550-235X}}, journal = {{Physical Review B}}, number = {{19}}, publisher = {{American Physical Society}}, title = {{{Optical response of stoichiometric and congruent lithium niobate from first-principles calculations}}}, doi = {{10.1103/PhysRevB.87.195208}}, volume = {{87}}, year = {{2013}}, } @article{13526, author = {{Eberhard, Jens and Stoll, Ion and Brockhinke, Regina and Neumann, Beate and Stammler, Hans-Georg and Riefer, Arthur and Rauls, Eva and Schmidt, Wolf Gero and Mattay, Jochen}}, issn = {{1466-8033}}, journal = {{CrystEngComm}}, number = {{21}}, title = {{{Structural variety of 5-fluoroarene-2-aminopyrimidine in comparison to 2-aminopyrimidine silver(i) coordination polymers: progress report and overview}}}, doi = {{10.1039/c2ce26388b}}, volume = {{15}}, year = {{2013}}, } @article{15867, author = {{Tautz, Raphael and Da Como, Enrico and Wiebeler, Christian and Soavi, Giancarlo and Dumsch, Ines and Fröhlich, Nils and Grancini, Giulia and Allard, Sybille and Scherf, Ullrich and Cerullo, Giulio and Schumacher, Stefan and Feldmann, Jochen}}, issn = {{0002-7863}}, journal = {{Journal of the American Chemical Society}}, pages = {{4282--4290}}, title = {{{Charge Photogeneration in Donor–Acceptor Conjugated Materials: Influence of Excess Excitation Energy and Chain Length}}}, doi = {{10.1021/ja309252a}}, year = {{2013}}, } @article{15866, author = {{Ardizzone, Vincenzo and Lewandowski, Przemyslaw and Luk, M. H. and Tse, Y. C. and Kwong, N. H. and Lücke, Andreas and Abbarchi, Marco and Baudin, Emmanuel and Galopin, Elisabeth and Bloch, Jacqueline and Lemaitre, Aristide and Leung, P. T. and Roussignol, Philippe and Binder, Rolf and Tignon, Jerome and Schumacher, Stefan}}, issn = {{2045-2322}}, journal = {{Scientific Reports}}, title = {{{Formation and control of Turing patterns in a coherent quantum fluid}}}, doi = {{10.1038/srep03016}}, year = {{2013}}, } @article{15868, author = {{Luk, M. H. and Tse, Y. C. and Kwong, N. H. and Leung, P. T. and Lewandowski, Przemyslaw and Binder, R. and Schumacher, Stefan}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, title = {{{Transverse optical instability patterns in semiconductor microcavities: Polariton scattering and low-intensity all-optical switching}}}, doi = {{10.1103/physrevb.87.205307}}, year = {{2013}}, } @article{4353, author = {{Schumacher, Stefan and Zrenner, Artur}}, issn = {{0277-786X}}, journal = {{ULTRAFAST PHENOMENA AND NANOPHOTONICS XVII}}, title = {{{Two-photon physics with quantum-dot biexcitons}}}, doi = {{10.1117/12.2004191}}, year = {{2013}}, } @article{15871, abstract = {{We derive a transparent and easy-to-use analytic expression for the selection rules and the optical dipole matrix elements for carbon nanotubes of arbitrary chirality in the presence of axial magnetic fields using a single-orbital π-electron tight-binding model. From this, we calculate the linear absorption spectrum for arbitrary polarization directions of the incident light, providing insight into all optically allowed transition. We show that the transverse absorption peaks can be selectively excited with circularly polarized light and spectrally resolved in an axial magnetic field.}}, author = {{Liu, Hong and Schumacher, Stefan and Meier, Torsten}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{3}}, title = {{{Selection rules and linear absorption spectra of carbon nanotubes in axial magnetic fields}}}, doi = {{10.1103/physrevb.88.035429}}, volume = {{88}}, year = {{2013}}, } @article{15870, author = {{Ling, Sanliang and Schumacher, Stefan and Galbraith, Ian and Paterson, Martin J.}}, issn = {{1932-7447}}, journal = {{The Journal of Physical Chemistry C}}, pages = {{6889--6895}}, title = {{{Excited-State Absorption of Conjugated Polymers in the Near-Infrared and Visible: A Computational Study of Oligofluorenes}}}, doi = {{10.1021/jp401359a}}, year = {{2013}}, } @inproceedings{63080, author = {{Fechner, Sabine and Kauertz, Alexander}}, booktitle = {{Inquiry-based Learning - Forschendes Lernen}}, editor = {{Bernholt, Sascha}}, publisher = {{IPN-Verlag}}, title = {{{Merkmale von Kontexten in Chemie und Physik}}}, year = {{2013}}, } @inproceedings{63085, author = {{Sumfleth, Elke and Harbach, Andrea and Fechner, Sabine}}, booktitle = {{Annual Meeting of the National Association for Research in Science Teaching [NARST], 6-9 April, Rio Grande, Puerto Rico, USA}}, title = {{{Investigating the effects of problem-orientation and interconnectedness in context-based learning tasks}}}, year = {{2013}}, } @article{13819, author = {{Riefer, A. and Sanna, S. and Schmidt, Wolf Gero}}, issn = {{0015-0193}}, journal = {{Ferroelectrics}}, pages = {{78--85}}, title = {{{LiNb1-xTaxO3Electronic Structure and Optical Response fromFirst-PrinciplesCalculations}}}, doi = {{10.1080/00150193.2013.821904}}, volume = {{447}}, year = {{2013}}, } @inbook{18475, abstract = {{The frequency-dependent dielectric function and the second-order polarizability tensor of ferroelectric LiNbO3 are calculated from first principles. The calculations are based on the electronic structure obtained from density-functional theory. The subsequent application of the GW approximation to account for quasiparticle effects and the solution of the Bethe–Salpeter equation yield a dielectric function for the stoichiometric material that slightly overestimates the absorption onset and the oscillator strength in comparison with experimental measurements. Calculations at the level of the independent-particle approximation indicate that these deficiencies are at least partially related to the neglect of intrinsic defects typical for the congruent material. The second-order polarizability calculated within the independent-particle approximation predicts strong nonlinear coefficients for photon energies above 1.5 eV. The comparison with measured data suggests that self-energy effects improve the agreement between experiment and theory. The intrinsic defects of congruent samples reduce the optical nonlinearities, in particular for the 21 and 31 tensor components, further improving the agreement with measured data.}}, author = {{Riefer, Arthur and Rohrmüller, Martin and Landmann, Marc and Sanna, Simone and Rauls, Eva and Vollmers, Nora Jenny and Hölscher, Rebecca and Witte, Matthias and Li, Yanlu and Gerstmann, Uwe and Schindlmayr, Arno and Schmidt, Wolf Gero}}, booktitle = {{High Performance Computing in Science and Engineering ‘13}}, editor = {{Nagel, Wolfgang E. and Kröner, Dietmar H. and Resch, Michael M.}}, isbn = {{978-3-319-02164-5}}, pages = {{93--104}}, publisher = {{Springer}}, title = {{{Lithium niobate dielectric function and second-order polarizability tensor from massively parallel ab initio calculations}}}, doi = {{10.1007/978-3-319-02165-2_8}}, year = {{2013}}, } @article{18476, abstract = {{We investigate the band dispersion and relevant electronic properties of rubrene single crystals within the GW approximation. Due to the self-energy correction, the dispersion of the highest occupied molecular orbital (HOMO) band increases by 0.10 eV compared to the dispersion of the Kohn-Sham eigenvalues within the generalized gradient approximation, and the effective hole mass consequently decreases. The resulting value of 0.90 times the electron rest mass along the Γ-Y direction in the Brillouin zone is closer to experimental measurements than that obtained from density-functional theory. The enhanced bandwidth is explained in terms of the intermolecular hybridization of the HOMO(Y) wave function along the stacking direction of the molecules. Overall, our results support the bandlike interpretation of charge-carrier transport in rubrene.}}, author = {{Yanagisawa, Susumu and Morikawa, Yoshitada and Schindlmayr, Arno}}, issn = {{1550-235X}}, journal = {{Physical Review B}}, number = {{11}}, publisher = {{American Physical Society}}, title = {{{HOMO band dispersion of crystalline rubrene: Effects of self-energy corrections within the GW approximation}}}, doi = {{10.1103/PhysRevB.88.115438}}, volume = {{88}}, year = {{2013}}, } @article{18479, abstract = {{The GW approximation for the electronic self-energy is an important tool for the quantitative prediction of excited states in solids, but its mathematical exploration is hampered by the fact that it must, in general, be evaluated numerically even for very simple systems. In this paper I describe a nontrivial model consisting of two electrons on the surface of a sphere, interacting with the normal long-range Coulomb potential, and show that the GW self-energy, in the absence of self-consistency, can in fact be derived completely analytically in this case. The resulting expression is subsequently used to analyze the convergence of the energy gap between the highest occupied and the lowest unoccupied quasiparticle orbital with respect to the total number of states included in the spectral summations. The asymptotic formula for the truncation error obtained in this way, whose dominant contribution is proportional to the cutoff energy to the power −3/2, may be adapted to extrapolate energy gaps in other systems.}}, author = {{Schindlmayr, Arno}}, issn = {{1550-235X}}, journal = {{Physical Review B}}, number = {{7}}, publisher = {{American Physical Society}}, title = {{{Analytic evaluation of the electronic self-energy in the GW approximation for two electrons on a sphere}}}, doi = {{10.1103/PhysRevB.87.075104}}, volume = {{87}}, year = {{2013}}, } @article{40403, author = {{Sharapova, Polina and Tikhonova, O V}}, issn = {{1612-2011}}, journal = {{Laser Physics Letters}}, keywords = {{Physics and Astronomy (miscellaneous), Instrumentation}}, number = {{7}}, publisher = {{IOP Publishing}}, title = {{{Coherent control of interaction and entanglement of a Rydberg atom with few photons}}}, doi = {{10.1088/1612-2011/10/7/075204}}, volume = {{10}}, year = {{2013}}, } @article{22952, author = {{Sternemann, E. and Jostmeier, T. and Ruppert, C. and Duc, H. T. and Meier, Torsten and Betz, M.}}, issn = {{1098-0121}}, journal = {{Physical Review B}}, number = {{16}}, title = {{{Femtosecond quantum interference control of electrical currents in GaAs: Signatures beyond the perturbative χ(3) limit}}}, doi = {{10.1103/physrevb.88.165204}}, volume = {{88}}, year = {{2013}}, } @inbook{64929, author = {{Mersch, Katharina Ulrike}}, booktitle = {{Rosenkränze und Seelengärten – Bildung und Frömmigkeit in niedersächsischen Frauenklöstern}}, editor = {{Kruse, Britta Juliane}}, pages = {{57--62}}, title = {{{Das Zusammenspiel von Klosterbibliothek und Kirchenausstattung im Augustiner-Chorfrauenstift Heiningen}}}, volume = {{96}}, year = {{2013}}, } @article{64930, author = {{Mersch, Katharina Ulrike}}, journal = {{Frühmittelalterliche Studien}}, pages = {{209--238}}, title = {{{Göttlich legitimierter Eigensinn. Gewissensfreiheit als Option im Umgang mit dem exkommunizierten Ludwig dem Bayern und dem Interdikt}}}, volume = {{47}}, year = {{2013}}, } @misc{64956, author = {{Mersch, Katharina Ulrike}}, booktitle = {{Niedersächsisches Jahrbuch für Landesgeschichte}}, pages = {{461--465}}, title = {{{Inschriften als Zeugnisse kulturellen Gedächtnisses. 40 Jahre Deutsche Inschriften in Göttingen. Beiträge zum Jubiläumskolloquium vom 22. Oktober 2010 in Göttingen, hrsg. von Nikolaus Henkel. Wiesbaden 2012 / Die Inschriften des Landkreises Holzminden, bearb. von Jörg H. Lampe und MeikeWilling. Wiesbaden 2012 (Die Deutschen Inschriften 83 / Göttinger Reihe 15)}}}, volume = {{85}}, year = {{2013}}, } @article{44794, author = {{Freitag, Christine and Tegeler, Eveline and Bohnhorst, Janina}}, journal = {{Informationes Theologiae Europae, Internationales ökumenisches Jahrbuch für Theologie, 17. Jahrgang 2008-2013}}, pages = {{199--222}}, publisher = {{Lang}}, title = {{{Wie Lehrkräfte über die Religion ihrer Schüler und Schülerinnen denken}}}, year = {{2013}}, }